一、解决方法
请求和响应时都要设置编码，需区分get/post请求，区分字节流和字符流输出。
-
对于post请求，需设置request.setCharacterEncoding("utf-8");
对于get请求，有以下两种方式：
(1) String sno = new String(request.getParameter("sno").getBytes("ISO8859-1"),"UTF-8");
(2)设置tomcat编码(测试环境tomcat7)，在server.xml对应位置加上URIEncoding="UTF-8"
1.png 对于get/post的响应
若为字节流，需加以下代码：
//让浏览器用utf8来解析返回的数据
response.setHeader("Content-type", "text/html;charset=UTF-8");
OutputStream ps = response.getOutputStream();
String data = sno + name;
//使得放入流的数据是utf8格式
ps.write(data.getBytes("UTF-8"));
若为字符流，需加以下代码
//让浏览器用utf8来解析返回的数据
response.setHeader("Content-type", "text/html;charset=UTF-8");
//设置服务器输出的编码为UTF-8，而不是用默认的ISO8859
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
out.println(sno);
out.println(name);
二、例子
public class Student {
private String sno;
private String name;
public String getSno() {
return sno;
}
public void setSno(String sno) {
this.sno = sno;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
@WebServlet(name = "FirstServlet", urlPatterns = "/firstServlet")
public class FirstServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
/* 对于post请求，该语句为避免中文参数乱码起到关键作用 */
request.setCharacterEncoding("utf-8");
String sno = request.getParameter("sno");
String name = request.getParameter("name");
System.out.println(sno + name);
//让浏览器用utf8来解析返回的数据
response.setHeader("Content-type", "text/html;charset=UTF-8");
////设置服务器输出的编码为UTF-8，而不是用默认的ISO8859
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
out.println(sno);
out.println(name);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String sno1 = request.getParameter("sno");
String name1 = request.getParameter("name");
System.out.println(sno1 + name1);
//get请求处理中文乱码
String sno = new String(request.getParameter("sno").getBytes("ISO8859-1"),"UTF-8");
String name = new String(request.getParameter("name").getBytes("ISO8859-1"),"UTF-8");
System.out.println(sno + name);
//让浏览器用utf8来解析返回的数据
response.setHeader("Content-type", "text/html;charset=UTF-8");
////设置服务器输出的编码为UTF-8，而不是用默认的ISO8859
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
out.println(sno);
out.println(name);
}
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>登录页面</title>
</head>
<body>
<div style="text-align: center">
<form action="/firstServlet" method="get">
<div>
学号： <input id="sno" name="sno"/>
</div>
<div>
姓名： <input id="name" name="name"/>
</div>
<div>
<input type="submit" value="登录"/>
<input type="reset" value="重置"/>
</div>
</form>
</div>
</body>
</html>
